Photographic-printing device



Oct. 27,1925

. A. G. OGDEN PHOTOGRAPHIC PRINTING DEVICE Filed March 5, 1921 A TTORUEB surface at a number of Patented Oct. 27, 1925. I

UNITED STATES PATENT OFFICE.

ASHLEY G. OGDEN, F BALTIMORE, MARYLAND, ASSIGNOR TO AMERICAN MKCHINE FOUNDRY COMPANY, A CORPORATION OF NEW JERSEY.

PHOTOGRAPHIC-PRINTING DEVICE.

Application filed March 5, 1921. Serial No. 449,801.

7 '0. all Irv/10121.2 may concern:

Be it known that I, ASHLEY G. OGDEN, a citizen of the United States, and a resident of Baltimore, county of Baltimore, and

tate of Maryland, have invented certain new and useful Improvements in Photographic-Printing Devices, of which the following is a specification.

This invention relates to photographic printing devices and is herein disclosed as applied to a multiple printing device adapt; ed to roduce plates for lithographic printing. ne form of such a device is shown in my Reissue Patent No. 14,517, dated September 3, 1918. Such plates are largely used in the artof lithography, especially for printing upon tin when it is desired from a single negative to produce a number of plates which shall be identical and shall be accurately registered with each other and with other plates which may be used for printing several colors uponthe same cans or other printing surfaces. In order to obtain the accurate registry in' producing such plates, the photographic printing devices employed are massive in construction and for purposes of economy in printing, they are often built large enough to accommodate a very large plate with the result that the handling of the negative and the sensitized surface are a tors.

In the devices to which the present invention is herein shown as applied, the sensitized plate is carried by ashiftable cradle or carrier over a table in which the negative is mounted, and mechanical devices of great accuracy in construction are usually employed to accurately center the sensitized ositions above the negative which is usual y mounted in the body of the table. In,making the exposures upon a sensitized surface to produce the desired plate, the surface is shifted across the table so that light coming from below up through the negative will make the desired exposure upon the plate. Thisshifting of the sensitized plate involves lifting it or its supports clear of the surface of the table, then shifting the sensitized surface carrier to the new position, with the result that unless aprons or other light intercepting devices are provided the sensitized surface may become. light-struck.

According to the present invention instead problem involving many fac of employing an apron or other device which has to be separately handled, or

which is likely to interfere with the smooth operation of the mechanism, the surface of the table may be provided with a resilient covering such as a pile fabric, preferably black, which tends to absorb light and which springs up slightly when the plate carrier is lifted to the slight extent required might fog the sensitized surface. The resiliency of the pile fabric makes it particularly effective in devices like the one disclosed in which the plate carrier has an up and'down motion when shifted transverse- -ly for printing each exposure. Other features and advantages will hereinafter appear.

In the accompanying drawings,

Figure 1 is a perspective view of a device of a general type shown in said reissue patent and embodying the present invention.

Figure 2 is a sectional side view of a detail showing the cradle on a larger scale.

Figure 3 is a bottom perspective view of part of the cradle and the frame therein showing the plush surfaces thereon.

The table 1 is usually of extremely massive construction having integral thereon a V-shaped rail 2 and a fiat rail 3 upon whlch slides a main or primary carriage The plate or sensitized surface 5 is carried in a plate-holder 6 which is supported upon the lugs 7 in-a holding device in the form of a frame 8 seated in a cradle having sides 8" and which forms part of a secondary carriage 9 slidable upon the main carriage 4r For the purpose of obtaining great accuracy in the operation of the mechanism the secondary carriage 9 runs upon a Vi-shaped rail 10 and a fiat rail 11 on .the main carriage and is slidable therealon by a'screw-drive shaft 12 like the screwrive shaft 13 'which serves to drive the main carriage on its rails 2 and 3. The cradle 8 therefore shifts the sensitized surface-5 handle 18.

across the flat top 21 of the table 1 according as it is moved by the main carriage 4 or the secondary carriag 9, or by both carriages,

The cradle and frame 8 are adapted to be raised and lowered in the secondary carriage 9 by links 14 which are connected to rock arms 15 fast upon shafts 16 connected by a link 17 to be operated by a The sensitized surface 5 is adapted to be pressed against a negative 18 (see Fig. 2) supported in an opening 19 in the table 1 by a pressurehead 19 against the tension of springs 20 which normally lift it clear of the negative. In ordinary use the desired print is made upon the sensitized surface by a lamp, not shown, beneath the table 1, the latter serving as a shield to prevent access of light to the sensitized surface except through the negative mounted in the table or shield. In order to prevent the entry of any light to the sensitized surfa e 5 s leakage under the frame 8 and across the top 21 of the table 1, the table top 21 is rovided with a cover adapted to intercept tlie light and yieldable, yet resilient enough to rise after being depressed. For this purpose the table top 21 is usually covered with a resilient fabric such as black plush having a fairly long pile, and held down to the table top in any suitable manner. The pile fabric is preferably applied in fairly wide breadths, so that there are only a few joints 22 where the fabric is joined, thus minimizing the likelihood of light leakage along the joints and minimizing the liability of the fabric to be caught up by the transversely moving cradle 8 or frame 8.

The fabric is diagrammatically illustrated at 23 in Figure 2, and as herein shown, there is also a corresponding layer 'of pile fabric 24 upon the lower faces of the cradle 8F and the frame. 8. The cradle and frame 8 may be only a few inches wide, but it is found that even-with a narrow cradle and frame 8, narrow widths of fabric 24 co-operating with a fabric 23 upon the table surface 21 are suflicient to prevent fogging by outside light of even a high speed glass plate, if such is used as the sensitized surface 5. Where a slower working sensitized surface is used one fabric face, as the pile fabric 24, may, he sometimes omitted. It has been found that a suitable black plush has a sufficiently lon pile to enable the cradle 8, to' be safely sliifted a large number of times in printing upon a glass plate at 5, without the need of mterposing the shield which has sometimes been used to cover the sensitized surface in the plate-holder to prevent it from being light-struck and which runs in slides 25.

This devlce therefore, enables rapid printing to be made upon a glass plate of 9.

number of images or prints from a single small negative. The present device is therefore, used for the rapid preparation of lithographic plates by printing from a single small negative a considerable number of reproductions thereof upon a fairly large rapid glass plate, and then making the slow printing zinc or other lithographic printing plate in a few long exposures from the glass plate thus prepared. \Vorking'in this way with the mechanism here disclosed, it has been found possible to accomplish the work of printing the final zinc or other plate in a fraction of an hour, instead of occupying perhaps a day as has hitherto been the case.

In order to facilitate the rapid use of the mechanism, the usual slidable section 26 of the table 1 is provided and is covered with the pile fabric 23. This section is easily re movable by sliding it out horizontally to enable the plate-holder and its support to be removed by sliding out horizontally in thepressure head 19 and the backof the plate-holder 6, the handle 29 for operating the pressure head may have a device where by it is automatically locked in position at any tension desired by the operator irrespective of the position of the pressure head. For this purpose the pressure head is operated in the usual manner by links 30 connected to an integral pair of rock arms31, which in turn are fast to a rock arm 32 connected bya link 33 to a rock arm 34-fast to the hamdle 29. The arrangement of parts is such that the handle 29 is slightly overthrown 1n pressing down the pressure head '19 and is arrested by a stop 35 when so overthrown, thus ineffect forming a toggle joint for In order to vary the length of the link- 33 to enable this to be accomplished under various circumstances, the link 33 is formed in two parts connected by a screw turnbuckle 36 which the operator soon learns to adjust rapidly to adjust the length of link to suit the particular conditions of each exposure.

The crack 37 around the edges of the plate support is usually covered with some lightexcluding material, omitted herein for clearness in' showing the underlying structure.

Hav ng thus described one embodiment of my invention, what I claim is:

egerting pressure through the pressure head 1 p 1. In a photographic printing device, the combination with a shield having an opening for a negative, of a sensitized surface holding device adapted to he shifted to a, plurality of printing positions across said shield to be exposed to the negative. a black pile surface on the shield. and ablack pile surface on the holding device adapted to lie against the first pile surface to form a light tight joint around the sensitized surface.

2. In a photographic printing device, the combination with a shield having an opening for a negative, of a sensitized surface holding device adjacent the shield, means for shifting a device across the shield to bring different portions of the sensitized surface to the negative, means for effecting separation between the shield and device to separate the sensitized surface from the negative, and a fabric having a resilient pile and lying upon the shield to prevent light from entering between the supporting device and the shield.

3. In a photographic printing device. the combination with a table forming a shield, of a main carriage shiftable transversely of the shield, a secondary carriage shiftable transversely on the main carriage, a cradle for supportinga sensitized surface and car- 'ried by the secondary carriage, a resilient light-excluding surface at the back of the cradle, with a resilient pile fabric surface upon the shield to co-operate with the frame surface to exclude light.

4;. In a photographic printing device, the combination with a shield forming negative support. of a plate-holder adapted 'to carry a sensitized surface, a resilient device normally holding the sensitized surface clear of the negative, a pressure device for pressing the surface to the negative, a cradle carrying the plate-holder, a pile fabric facing on said plate-holder and a pile fabric facing on the shield so that the two pile fabrics form a light-excluding device.

In a photographic printing device the combination with a shield forming negative support, of a plate-holder adapted to carry a sensitized surface, aresilient device normally holding the sensitized surface clear of the negative. :1 pressure device for pressing the surface to the negative, a cradle carrying the plate-holder, a pile fabric facing on said plate-holder, a pile fabric facing on the shield so that the two pile fabrics form a light-excluding device, a main carriage for shifting the cradle across the shield, a secondary carriage for carrying the cradle across the main carriage, and means for lifting the cradle in the secondary carriage.

6. In a photographic printing device the combination with a table forming a shield adapted to support a negative, of a cradle adapted to support a plate-holder carrying a sensitized surface, a main carriage slidable across the shield, a secondary carriage slidable across the main carriage and transversely thereof, and resilient light-excluding surfaces upon the cradle and the shield adapted to exclude light from the sensitized surface.

7. In a photographic printing device, the combination with a table forming a shield. adapted to support a negative, of a cradle adapted to support a plate-holder carrying a sensitized surface, a main'carriage slidable across the shield, a secondary carriage slidable across the main carriage and transversely thereof, resilient light-excluding surfaces upon thecradle and the shield adapted to exclude light from the sensitized surface. resilient means normally holding the sensitized surface clear of the negative in the cradle, and means for lifting the cradle from the shield sufficiently to facilitate transverse shifting of the cradle upon the shield.

8. In a photographic printing device, the combination with a support adapted to support a negative, of a holder adapted to normally support a sensitized surface clear of the negative and means for effecting movement of the surface and the negative,

relatively toward and away from each other, i

and yieldable material so extending between the support and holder as to exclude light from the sensitized surface.

9. In a photographic printing device, the combination with a shield forming a negative support adapted to support a negative, of a holding device adapted to normally hold a sensitized surface clear of the negative, means for effecting movement of the surface and the negative relatively toward and away from each other, and yieldable material so carried by the support and holding device as to exclude light from the sensitizing surface.

10. In a photographic printing device. supports adapted to support a negative and a sensitized plate respectively, said supports having plane cooperative surfaces whereby one may be moved over the other, and a covering of long pile resilient fabric disposed between the two supports and adapt-- ed toexclude light from the sensitized plate.

11. The combination in a photographic printing device, supports adapted to support a negative and sensitized plate respectively, said supports having plane cooperative surfaces whereby one may be moved over the other, and a covering of pile fabric secured to said surfaces intermediate said supports and adapted to exclude light from the sensitized plate.

12. In a photographic printing device, the

combination with a support adapted to support a negative, of a holder adapted to normally support a sensitized surface clear of the negative, meansfor effecting movement of the surface and the negative relatively toward and awayfrom each other, and yield able material so arranged around the sensitized surface and extending between the support and holder as to exclude light from the sensitized surface.

13. In a photographic printing device, the combination with a support adapte to support a negative, of a holder adaptet to normally hold a sensitizedsurface clear of the negative means for effecting movement of the surface and the negative, relatively toward and away from each-other, and yieldable material so surrounding the negative and sensitized surface and extending between the support and holder as to exclude light from the sensitized surface. I

14. In a photographic printing device,

supports adapted to support a negative and Ya sensitized plate respectively, said supports having plane cooperative surfaces whereby one may be moved over the other, and yieldable material extending between said supports to exclude light from said sensitized plate.

15. In a photographic printing device, supports adapted to support a negative and a sensitized surface respectively, said suports having plane cooperative surfaces whereby one may be moved over the other,

and yieldable resilient material so extending between said supports as to surround said negative and sensitized surface for the purpose of excluding light therefrom. y

In testimonv whereof, I have afiixed my signature to this specification.

ASHLEY GQOGDEN 

